Connecting structure for shoe drying machine

ABSTRACT

A connecting structure for a shoe drying machine, including wind pipes fixed at output ends of the shoe drying machine, and shoe supports detachably connected to the wind pipes; each of the shoe supports sleeves a peripheral surface of a corresponding wind pipe, and a side wall of each of the shoe supports is provided with a first connecting part; a side wall of each of the wind pipes is provided with a second connecting part, and the second connecting part of each wind pipe and the first connecting part of a corresponding shoe support are locked with respect to each other by rotation of the corresponding shoe support.

BACKGROUND OF THE INVENTION

The present invention relates to the technical field of shoe drying machines, and in particular to a connecting structure of a shoe drying machine.

A shoe drying machine is a specially designed small household appliance for drying shoes, and is also called a shoe dryer, a shoe warmer or the like. A shoe drying machine can output hot air through an inner heating device, dry moisture in shoes through the hot air, and achieve the effects of sterilization, deodorization and the like.

In order to adapt to different shoes with different heights, such as low-top shoes, high-top shoes, tall boots and the like, a shoe support used for hanging a shoe upside down in a shoe drying machine is generally designed to be detachably connected with a wind pipe of the shoe drying machine, such that a single shoe drying machine can be adapted to different shoe supports of different sizes and shapes. In the prior art, connection between a shoe support and a wind pipe is mainly interference fit, and such connection has the following drawbacks:

-   -   (1) Interference fit create extremely large friction when the         shoe support is connected to or disconnected from the wind pipe,         and such operation is inconvenient, labor-consuming and         time-consuming; and     -   (2) Interference fit allows only a small contact surface between         the shoe support and the wind pipe. When the shoe support is         long, for example, when a long shoe support used for hanging a         tall boot upside down is connected to the wind pipe, the         friction between the shoe support and the wind pipe is weakened,         and thus the shoe support cannot be tightly fixed at an upper         end of the wind pipe due to the fact that a peripheral surface         of a lower end of the shoe support expands when being heated         during the drying process. In this case, when taking out the         tall boot from the shoe support after drying, the shoe support         is usually caused to be inclined and will be easily loosened         from the wind pipe and being taken out as well together with the         tall boot. Accordingly, user may further need to remove the shoe         support from the tall boot, and hence resulting in poor user's         experience.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to provide a connecting structure of a shoe drying machine, which can achieve firm connection between a shoe support and a wind pipe and axially limit the shoe support relative to the wind pipe to prevent the shoe support from being disengaged from the wind pipe. The present invention has a simple structure and is convenient to operate.

To achieve the above object, the present invention provides the following technical solutions:

A connecting structure for a shoe drying machine, comprising wind pipes fixed at output ends of the shoe drying machine, and shoe supports detachably connected to the wind pipes, wherein each of the shoe supports sleeves a peripheral surface of a corresponding wind pipe, and a side wall of each of the shoe supports is provided with a first connecting part; a side wall of each of the wind pipes is provided with a second connecting part, and the second connecting part of each wind pipe and the first connecting part of a corresponding shoe support are locked with respect to each other by rotation of the corresponding shoe support.

An upper end surface of each of the wind pipes is provided with a plurality of air outlets.

Each first connecting part comprises a first axial groove extending along an axial direction of the shoe support, and a first circumferential groove disposed along a circumferential direction of the shoe support, wherein a lower end of the first axial groove extends to a bottom end of the shoe support, and one end of the first circumferential groove is in communication with an upper end of the first axial groove; the second connecting part of each of the wind pipes comprises at least one first protruding piece arranged on an outer side wall of the wind pipe; when sleeving the shoe support on a corresponding wind pipe, the first protruding piece enters the first axial groove and reaches said one end of the first circumferential groove in communication with the upper end of the first axial groove, and when the shoe support further rotates on the corresponding wind pipe causing circumferential displacement of the first circumferential groove, the first protruding piece moves to lock at another end of the first circumferential groove, thereby achieving locking between the second connecting part and the first connecting part by rotation of the shoe support.

Preferably, a limiting bar is arranged between two ends of the first circumferential groove; the limiting bar is transversely positioned in the first circumferential groove such that both upper and lower ends of the limiting bar are connected to upper and lower walls of the first circumferential groove; two first protruding pieces are provided; when the second connecting part is locked with the first connecting part, the two first protruding pieces are locked on two sides of the limiting bar respectively.

Preferably, a distal end of at least one of the first protruding pieces is shaped as a rounded corner.

Preferably, two sides of the limiting bar are provided with inclined guiding planes respectively to facilitate slidable movements of the first protruding piece.

The first axial groove and the first circumferential groove both penetrate through an outer side wall of the shoe support along a radial direction of the shoe support.

Preferably, an upper wall of the first protruding piece is provided with a limiting protrusion, an upper wall of the first circumferential groove is provided with a first limiting groove corresponding to the limiting protrusion, and the limiting protrusion is removably inserted into the first limiting groove.

The connecting structure further comprises at least one extension pipe, wherein a lower end of each extension pipe is provided with a third connecting part having a same structure as the first connecting part, and an outer wall of an upper end of the extension pipe is provided with a fourth connecting part having a same structure as the second connecting part.

Preferably, the third connecting part of each extension pipe comprises a second axial groove extending along an axial direction of the extension pipe, and a second circumferential groove disposed along a circumferential direction of the extension pipe, wherein a lower end of the second axial groove extends to a bottom end of the extension pipe, and one end of the second circumferential groove is in communication with an upper end of the second axial groove; the fourth connecting part comprises a second protruding piece provided on an outer wall of the extension pipe.

Preferably, another end of the second circumferential groove of the third connecting part of each extension pipe is provided with a second limiting groove; the second connecting part of a corresponding wind pipe is removably inserted into the second limiting groove.

Each shoe support comprises a supporting frame and a connecting pipe, wherein the supporting frame has a shoe support shape or a palm shape; a lower end of the connecting pipe is provided with the first connecting part.

Preferably, an upper end of the connecting pipe is provided with a fifth connecting part; a lower end of the supporting frame is inserted into the upper end of the connecting pipe; an outer wall of the supporting frame is provided with a sixth connecting part locked with the fifth connecting part by circumferential displacement of the fifth connecting part; the supporting frame and the connecting pipe are locked with respect to each other through the fifth connecting part and the sixth connecting part by circumferential displacement of the fifth connecting part respect to the sixth connecting part so that the sixth connecting part is locked into the fifth connecting part.

Preferably, the supporting frame is provided with slots that allow the upper end of a corresponding connecting pipe to be inserted into.

By using the above technical solutions, the present invention achieves the following technical effects:

-   -   (1) Each shoe support sleeves the peripheral surface of a         corresponding wind pipe instead of being inserted into the wind         pipe, such that hot air will not leak out between the shoe         support and the wind pipe when flowing upwards, and thus drying         efficiency is ensured.     -   (2) The first connecting part and the second connecting part         locked with respect to each other through circumferential         displacement of the first connecting part with respect to the         second connecting part ensures that the first connecting part         and the second connecting part always keep the shoe support         axially limited along an axial direction of the wind pipe, given         that the shoe support is not rotated, thereby achieving firm         connection between the shoe support and the wind pipe, and the         shoe support is prevented from being disengaged from the wind         pipe.     -   (3) The present invention has a simple structure, and due to a         detachable connection due to said circumferential displacement         of a component with respect to another component, the wind pipe         and the shoe support are no longer connected by interference         fit, disassembly and assembly are more convenient when in use,         and operation is labor-saving; further, due to connection by         circumferential displacement of a component with respect to         another component, the first connecting part and the second         connecting part are not limited to be arranged at end positions         of the shoe support and the wind pipe respectively, so that         design is more flexible, and the farther the first connecting         part and the second connecting part are positioned away from the         end positions of the shoe support and the wind pipe         respectively, the more firmly the two are connected, and the         shoe support is less easily to incline relative to the wind         pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of Embodiment I of the present invention;

FIG. 2 is an exploded view of Embodiment I of the present invention;

FIG. 3 is a cross-sectional view of Embodiment I of the present invention;

FIG. 4 is an enlarged view of portion A in FIG. 3 ;

FIG. 5 is a perspective view of Embodiment II of the present invention;

FIG. 6 is an exploded view of Embodiment II of the present invention;

FIG. 7 is an enlarged view of portion B in FIG. 6 ;

FIG. 8 is an enlarged view of portion C in FIG. 6 ;

FIG. 9 is a perspective view of Embodiment III of the present invention;

FIG. 10 is an exploded view of Embodiment III of the present invention;

FIG. 11 is an enlarged view of portion D in FIG. 10 ;

FIG. 12 is a perspective view of Embodiment IV of the present invention;

FIG. 13 is an exploded view of Embodiment IV of the present invention;

FIG. 14 is a perspective view of a shoe support of Embodiment V of the present invention;

FIG. 15 is an exploded view of a shoe support of Embodiment V of the present invention; and

FIG. 16 is a front view of a supporting frame of Embodiment V of the present invention.

REFERENCE NUMERALS IN THE FIGURES

-   -   1—wind pipe; 11—second connecting part; 111—first protruding         piece; 112—rounded corner; 113—limiting protrusion; 12—air         outlet;     -   2—shoe support; 2 a—supporting frame; 2 b—connecting pipe;         21—first connecting part; 211—first axial groove; 212—first         circumferential groove; 213—limiting bar; 214—inclined guiding         plane; 215—first limiting groove; 22—fifth connecting part;         23—sixth connecting part; 231—third protruding piece; 24—slot;     -   3—extension pipe; 31—third connecting part; 311—second axial         groove; 312—second circumferential groove; 313—second limiting         groove; 32—fourth connecting part; 321—second protruding piece;     -   10—shoe drying machine.

DETAILED DESCRIPTION OF THE INVENTION

In order to further explain the technical solutions of the present invention, the present invention will be explained in detail by the specific embodiments.

Referring to FIGS. 1 to 16 , disclosed is a connecting structure of a shoe drying machine, comprising wind pipes 1 fixed at output ends of a shoe drying machine 10, and shoe supports 2 detachably connected to the wind pipes 1, wherein:

each of the shoe supports 2 sleeves a peripheral surface of a corresponding wind pipe 1, and a side wall of each of the shoe supports 2 is provided with a first connecting part 21;

a side wall of each of the wind pipes 1 is provided with a second connecting part 11, and the second connecting part 11 and the first connecting part 21 of a corresponding shoe support 2 are locked with respect to each other by rotation of the corresponding shoe support 2.

In some embodiments of the present invention, an upper end surface of each of the wind pipes 1 is provided with a plurality of air outlets 12, such that the upper end surface of the wind pipe 1 forms a mesh structure, thereby preventing foreign matters from falling into the shoe drying machine 10; and meanwhile, the air outlets 12 are formed in the upper end surface of the wind pipe 1, such that hot air can be directly outputted along an axial direction of the wind pipe 1, and the hot air flows more smoothly.

In some embodiments of the present invention, referring to FIGS. 2 and 8 , each first connecting part 21 comprises a first axial groove 211 extending along an axial direction of the corresponding shoe support 2, and a first circumferential groove 212 disposed along a circumferential direction of the corresponding shoe support 2, wherein a lower end of the first axial groove 211 extends to a bottom end of the shoe support 2, and one end of the first circumferential groove 212 is in communication with an upper end of the first axial groove 211; in other words, the first connecting part 21 has an L-shape; the second connecting part 11 of each of the wind pipes 1 comprises at least one first protruding piece 111 arranged on an outer wall of the wind pipe 1; when sleeving the shoe support 2 on a corresponding wind pipe 1, the first protruding piece 111 enters the first axial groove 211 and reaches said one end of the first circumferential groove 212 in communication with the upper end of the first axial groove 211, and when the shoe support 2 further rotates on the corresponding wind pipe 1 causing circumferential displacement of the first circumferential groove 212, the first protruding piece 111 moves to lock at another end of the first circumferential groove 212, thereby achieving locking between the second connecting part 11 and the first connecting part 21 by rotation of the shoe support 2.

In some embodiments of the present invention, the present invention further comprises at least one extension pipe 3, wherein a lower end of each extension pipe 3 is provided with a third connecting part 31 having a same structure as the first connecting part 21, and an outer wall of an upper end of the extension pipe 3 is provided with a fourth connecting part 32 having a same structure as the second connecting part 11. When a length of the wind pipe 1 of the shoe drying machine 10 cannot meet a use requirement, at least one extension pipe 3 is connected between the wind pipe 1 and the corresponding shoe support 2, so as to increase a height of the shoe support 2 relative to a base of the shoe drying machine 10, thereby meeting a drying requirement of shoes such as tall boots or the like; further, as the third connecting part 31 has the same structure as the first connecting part 21, and the fourth connecting part 32 has the same structure as the second connecting part 11, a plurality of extension pipes 3 can be similarly connected to one another through mutual engagement of the third connecting part 31 of one extension pipe 3 with a corresponding fourth connecting part 32 of another extension pipe 3.

Furthermore, referring to FIGS. 10 and 11 , the third connecting part 31 of each extension pipe 3 comprises a second axial groove 311 extending along an axial direction of the extension pipe 3, and a second circumferential groove 312 disposed along a circumferential direction of the extension pipe 3, wherein a lower end of the second axial groove 311 extends to a bottom end of the extension pipe 3, and one end of the second circumferential groove 312 is in communication with an upper end of the second axial groove 311; in other words, the third connecting part 31 and the first connecting part 21 are both in an L-shape; the fourth connecting part 32 of each extension pipe 3 is a second protruding piece 321 disposed on an outer wall of the extension pipe 3. In other words, both the fourth connecting part 32 and the second connecting part 11 are protruding pieces. As explained above, an L-shaped connecting part allows a protruding piece to be inserted therein, and by circumferential displacement of the L-shaped connecting part caused by rotation, the protruding piece is moved to lock with the L-shaped connecting part. Therefore, the second connecting part 11 of the wind pipe 1 is locked with the third connecting part 31 of the extension pipe 3 by circumferential displacement of the third connecting part 31, and the fourth connecting part 32 of the extension pipe 3 is locked with the first connecting part 21 of the shoe support 2 by circumferential displacement of the first connecting part 21, thereby achieving a sequential connection between the wind pipe 1, the extension pipe 3 and the shoe support 2. Further, a plurality of extension pipes 3 can also be connected and thus locked to one another through mutual engagement of the third connecting part 31 of one extension pipe 3 with a corresponding fourth connecting part 32 of another extension pipe 3 by circumferential displacement of the former against the latter.

In some embodiments of the present invention, each shoe support 2 comprises a supporting frame 2 a and a connecting pipe 2 b, wherein the supporting frame 2 a may be in a shoe support shape or a palm shape according to different product requirements; a lower end of the connecting pipe 2 b is provided with the first connecting part 21. Besides, according to different product designs, the supporting frame 2 a and the connecting pipe 2 b can be integrated as a whole or separately made but connected to each other, and for the latter case, the supporting frame 2 a can be disassembled so that different types of supporting frames 2 a can be exchanged and replaced.

Furthermore, an upper end of the connecting pipe 2 b is provided with a fifth connecting part 22 having a same structure as the first connecting part 21; a lower end of the supporting frame 2 a is inserted into the upper end of the connecting pipe 2 b; an outer wall of the supporting frame 2 a is provided with a sixth connecting part 23 locked with the fifth connecting part 22 by circumferential displacement of the fifth connecting part 22; the sixth connecting part 23 comprises at least one third protruding piece 231. By locking the sixth connecting part 23 into the fifth connecting part 22 by circumferential displacement of the fifth connecting part 22, detachable connection between the supporting frame 2 a and the connecting pipe 2 b can be achieved, thereby facilitating replacement of a different supporting frame 2 a according to different use requirements.

In some embodiments of the present invention, each wind pipe 1 may be integrally formed on an upper surface of the shoe drying machine 10, or may be detachably mounted on the upper surface of the shoe drying machine 10 by threaded connection or the like. Since the wind pipe 1 is generally not required to be disassembled, convenience of using the product is not influenced by said threaded connection.

Referring to FIGS. 1 to 4 , Embodiment I of the present invention is shown.

In Embodiment I, each wind pipe 1 is a long pipe piece, and two wind pipes are provided; each shoe support 2 is an integral piece, namely, the supporting frame 2 a and the connecting pipe 2 b are integrally formed by injection molding; the supporting frame 2 a is in a shoe support shape; and no extension pipe 3 is used in Embodiment I.

In Embodiment I, the first connecting part 21 is a groove recessed on an inner side wall of the connecting pipe 2 b, and a limiting bar 213 is arranged between two ends of the first circumferential groove 212; the limiting bar 213 is transversely positioned in the first circumferential groove 212 such that both upper and lower ends of the limiting bar 213 are connected to upper and lower walls of the first circumferential groove 212; two first protruding pieces 111 are provided. When the second connecting part 11 is locked with the first connecting part 21, the two first protruding pieces 111 are locked on two sides of the limiting bar 213 respectively. The two first protruding pieces 111 locking on two sides of the limiting bar 213 prevent circumferential rotation of the shoe support 2 relative to the wind pipe 1, so that the shoe support 2 is ensured not to easily rotate unless a relatively strong external force is applied. Further, a width of the first axial groove 211 is no less than a distance between distal ends of the two first protruding pieces 111, such that the two first protruding pieces 111 can be simultaneously inserted into the first axial groove 211 when the shoe support 2 sleeves onto the wind pipe 1.

Furthermore, referring to FIG. 4 , the distal end of at least one of the first protruding pieces 111 are shaped as rounded corner 112, and the rounded corner 112 are designed to reduce resistance of the first protruding piece 111 against the limiting bar 213 when moving over the limiting bar 213 during locking, so that locking operation is eased while still ensuring that the shoe support 2 cannot easily rotate at the locked position.

Secondly, two sides of the limiting bar 213 are provided with inclined guiding planes 214 respectively to facilitate slidable movements of the first protruding piece 111 and achieve a similar effect like the rounded corner 112 so that the first protruding piece 111 can conveniently moving over the limiting bar 213 when subject to a relatively strong external force.

Referring to FIGS. 5 and 6 , Embodiment II of the present invention is shown.

In Embodiment II, each wind pipe 1 is a long pipe piece, two wind pipes are provided; each shoe support 2 is an integral piece, namely, the supporting frame 2 a and the connecting pipe 2 b are integrally formed by injection molding; the supporting frame 2 a is in a shoe support shape; and no extension pipe 3 is used in Embodiment II. Embodiment II mainly differs from Embodiment I in the structure of the first connecting part 21.

In Embodiment II, the first connecting part 21 is formed as a notch penetrating through an inner side wall and an outer side wall of the connecting pipe 2 b. In other words, the first axial groove 211 and the first circumferential groove 212 both penetrate through an outer side wall of the shoe support 2 along a radial direction of the shoe support 2, such that the first connecting part 21 is formed as an L-shaped notch on the shoe support 2; correspondingly, a thickness of the first protruding piece 111 is greater compared with that in Embodiment I, thereby achieving a better limiting effect since the first protruding piece 111 is prevented from being disengaged from the first circumferential groove 212 due to expansion in size of the shoe support 2 caused by heat during drying.

Furthermore, referring to FIGS. 7 and 8 , an upper wall and/or a lower wall of the first protruding piece 111 is provided with a limiting protrusion 113, an upper wall and/or a lower wall of the first circumferential groove 212 is provided with a first limiting groove 215 corresponding to the limiting protrusion 113, and the limiting protrusion 113 is removably inserted into the first limiting groove 215, so as to limit a circumferential rotation of the first connecting part 21 relative to the second connecting part 11, and hence prevent the wind pipe 1 and the corresponding shoe support 2 from rotating with respect to each other after being assembled.

Referring to FIGS. 9 to 11 , Embodiment III of the present invention is shown.

In Embodiment III, each wind pipe 1 is a short pipe piece, and four wind pipes are provided; each shoe support 2 is an integral piece, namely, the supporting frame 2 a and the connecting pipe 2 b are integrally formed by injection molding; the supporting frame 2 a is in a shoe support shape; and in Embodiment III, no extension pipe 3 is used between two of the wind pipes 1 and the corresponding two shoe supports 2, and extension pipes 3 are used between another two wind pipes 1 and the corresponding two shoe support 2.

In Embodiment III, another end of the second circumferential groove 312 of the third connecting part 31 of each extension pipe 3 is provided with a second limiting groove 313, the second connecting part 11 of a corresponding wind pipe 1 or the fourth connecting part 32 of an another adjacent extension pipe 3 is removably inserted into the second limiting groove 313, such that the extension pipe 3 can be prevented from rotating relative to the corresponding wind pipe 1 or said another adjacent extension pipe 3 after being assembled.

Referring to FIGS. 12 and 13 , Embodiment IV of the present invention is shown.

In Embodiment IV, each wind pipe 1 is a long pipe piece, and two wind pipes are provided; the shoe support 2 is an assembled structure, namely, the supporting frame 2 a and the connecting pipe 2 b are locked with respect to each other through the fifth connecting part 22 and the sixth connecting part 23 by circumferential displacement of the fifth connecting part 22 respect to the sixth connecting part 23 so that the sixth connecting part 23 is locked into the fifth connecting part 22; the supporting frame 2 a is in a shoe support shape; and no extension pipe 3 is used in Embodiment IV.

Referring to FIGS. 14 to 16 , Embodiment V of the present invention is shown, which mainly shows another embodiment of the shoe support 2.

In Embodiment V, each shoe support 2 has an assembled structure, namely, the supporting frame 2 a and the connecting pipe 2 b are locked with respect to each other through the fifth connecting part 22 and the sixth connecting part 23 by circumferential displacement of the fifth connecting part 22 respect to the sixth connecting part 23 so that the sixth connecting part 23 is locked into the fifth connecting part 22. The shoe support 2 of Embodiment V differs from that of Embodiment IV in that: the supporting frame 2 a has a palm shape, and the supporting frame 2 a is provided with slots 24 that allow the upper end of a corresponding connecting pipe 2 b to be inserted into, such that connection between the connecting pipe 2 b and the supporting frame 2 a is more stable.

Through the above technical solutions, each shoe support 2 sleeves the peripheral surface of a corresponding wind pipe 1 instead of being inserted into the wind pipe 1, such that hot air will not leak out between the shoe support 2 and the wind pipe 1 when flowing upwards, and thus drying efficiency is ensured; the first connecting part 21 and the second connecting part 11 locked with respect to each other through circumferential displacement of the first connecting part 21 with respect to the second connecting part ensures that the first connecting part 21 and the second connecting part 11 always keep the shoe support 2 axially limited along an axial direction of the wind pipe 1, given that the shoe support 2 is not rotated, thereby achieving firm connection between the shoe support 2 and the wind pipe 1, and the shoe support 2 is prevented from being disengaged from the wind pipe 1. The present invention has a simple structure, and due to a detachable connection due to said circumferential displacement of a component with respect to another component, the wind pipe 1 and the shoe support 2 are no longer connected by interference fit, disassembly and assembly are more convenient when in use, and operation is labor-saving; further, due to connection by circumferential displacement of a component with respect to another component, the first connecting part 21 and the second connecting part 11 are not limited to be arranged at end positions of the shoe support 2 and the wind pipe 1 respectively, so that design is more flexible, and the farther the first connecting part 21 and the second connecting part 11 are positioned away from the end positions of the shoe support 2 and the wind pipe 1 respectively, the more firmly the two are connected, and the shoe support 2 is less easily to incline relative to the wind pipe 1.

The above embodiments and drawings are not intended to limit the form and style of the product of the present invention, and any suitable changes or modifications made by those of ordinary skill in the art shall fall within the patent scope of the present invention. 

What is claimed is:
 1. A connecting structure for a shoe drying machine, comprising: wind pipes fixed at output ends of the shoe drying machine, and shoe supports detachably connected to the wind pipes, wherein each of the shoe supports sleeves a peripheral surface of a corresponding wind pipe, and a side wall of each of the shoe supports is provided with a first connecting part; a side wall of each of the wind pipes is provided with a second connecting part, and the second connecting part of each wind pipe and the first connecting part of a corresponding shoe support are locked with respect to each other by rotation of the corresponding shoe support.
 2. The connecting structure of claim 1, wherein an upper end surface of each of the wind pipes is provided with a plurality of air outlets.
 3. The connecting structure of claim 1, wherein each first connecting part comprises a first axial groove extending along an axial direction of the shoe support, and a first circumferential groove disposed along a circumferential direction of the shoe support; a lower end of the first axial groove extends to a bottom end of the shoe support, and one end of the first circumferential groove is in communication with an upper end of the first axial groove; the second connecting part of each of the wind pipes comprises at least one first protruding piece arranged on an outer side wall of the wind pipe; when sleeving the shoe support on a corresponding wind pipe, the first protruding piece enters the first axial groove and reaches said one end of the first circumferential groove in communication with the upper end of the first axial groove, and when the shoe support further rotates on the corresponding wind pipe causing circumferential displacement of the first circumferential groove, the first protruding piece moves to lock at another end of the first circumferential groove, thereby achieving locking between the second connecting part and the first connecting part by rotation of the shoe support.
 4. The connecting structure of claim 3, wherein a limiting bar is arranged between two ends of the first circumferential groove; the limiting bar is transversely positioned in the first circumferential groove such that both upper and lower ends of the limiting bar are connected to upper and lower walls of the first circumferential groove; two first protruding pieces are provided; when the second connecting part is locked with the first connecting part, the two first protruding pieces are locked on two sides of the limiting bar respectively.
 5. The connecting structure of claim 4, wherein a distal end of at least one of the first protruding pieces is shaped as a rounded corner.
 6. The connecting structure of claim 5, wherein two sides of the limiting bar are provided with inclined guiding planes respectively to facilitate slidable movements of the first protruding piece.
 7. The connecting structure of claim 3, wherein the first axial groove and the first circumferential groove both penetrate through an outer side wall of the shoe support along a radial direction of the shoe support.
 8. The connecting structure of claim 7, wherein an upper wall of the first protruding piece is provided with a limiting protrusion, an upper wall of the first circumferential groove is provided with a first limiting groove corresponding to the limiting protrusion, and the limiting protrusion is removably inserted into the first limiting groove.
 9. The connecting structure of claim 3, wherein the connecting structure further comprises at least one extension pipe, wherein a lower end of each extension pipe is provided with a third connecting part having a same structure as the first connecting part, and an outer wall of an upper end of the extension pipe is provided with a fourth connecting part having a same structure as the second connecting part.
 10. The connecting structure of claim 9, wherein the third connecting part of each extension pipe comprises a second axial groove extending along an axial direction of the extension pipe, and a second circumferential groove disposed along a circumferential direction of the extension pipe, wherein a lower end of the second axial groove extends to a bottom end of the extension pipe, and one end of the second circumferential groove is in communication with an upper end of the second axial groove; the fourth connecting part comprises a second protruding piece provided on an outer wall of the extension pipe.
 11. The connecting structure of claim 10, wherein another end of the second circumferential groove of the third connecting part of each extension pipe is provided with a second limiting groove; the second connecting part of a corresponding wind pipe is removably inserted into the second limiting groove.
 12. The connecting structure of claim 3, wherein each shoe support comprises a supporting frame and a connecting pipe, wherein the supporting frame has a shoe support shape or a palm shape; a lower end of the connecting pipe is provided with the first connecting part.
 13. The connecting structure of claim 12, wherein an upper end of the connecting pipe is provided with a fifth connecting part; a lower end of the supporting frame is inserted into the upper end of the connecting pipe; an outer wall of the supporting frame is provided with a sixth connecting part locked with the fifth connecting part by circumferential displacement of the fifth connecting part; the supporting frame and the connecting pipe are locked with respect to each other through the fifth connecting part and the sixth connecting part by circumferential displacement of the fifth connecting part respect to the sixth connecting part so that the sixth connecting part is locked into the fifth connecting part.
 14. The connecting structure of claim 13, wherein the supporting frame is provided with slots that allow the upper end of a corresponding connecting pipe to be inserted into. 